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Subject: Re: [PATCH 2/3] x86/mm: introduce __PAGE_KERNEL_GLOBAL
To:     Nadav Amit <nadav.amit@gmail.com>
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From:   Dave Hansen <dave.hansen@linux.intel.com>
Message-ID: <a3dd1676-a2dc-aa02-77ad-51cd3b7a78d5@linux.intel.com>
Date:   Fri, 16 Feb 2018 10:03:50 -0800
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On 02/16/2018 09:47 AM, Nadav Amit wrote:
>> But, this also means that we now get *no* opportunity to use
>> global pages with PTI, even for data which is shared such as the
>> cpu_entry_area and entry/exit text.
> 
> Doesn’t this patch change the kernel behavior when the “nopti”
> parameter is used?

I don't think so.  It takes the "nopti" behavior and effectively makes
it apply everywhere.  So it changes the PTI behavior, not the "nopti"
behavior.

Maybe it would help to quote the code that you think does this instead
of the description. :)